CBSE Class 11-science Answered
Alpha particle an electrically charged ( + ) particle emitted from the nucleus of some radioactive chemicals, cf. plutonium. It contains 2 protons and 2 neutrons, and is the largest of the atomic particles emitted by radioactive chemicals. It can cause ionisation.
Beta particle an electrically charged ( - ) particle emitted from some radioactive chemicals. It has the mass of an electron. Krypton 85, emitted from nuclear power plants, is a strong beta emitter. Beta particles can cause ionisation.
Gamma ray short wave-length electromagnetic radiation released by some nuclear transformations. It is similar to X-ray and will penetrate through the human body. Iodine 131 emits gamma rays. Both gamma and X-rays cause ionisation.
Gamma rays are electromagnetic waves. We cannot see gamma rays and, in fact, they are the smallest rays within the electromagnetic spectrum.
Because gamma rays are photons (small packets of energy), they have to be emitted by a source that produces energy. Thus, radioactive atoms are used to emit gamma rays (cobalt-60 and potassium-40). There are machines that produce gamma rays using the radioactive atoms in laboratories and hospitals. The machines work a lot like X-ray machines, but they are more powerful.
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